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HRTF Selection issue

I recently upgraded to Max 6.1. Since I have done this I am having a problem with the abstraction spat.hrtf.selection.maxpat which is used in the help example for spat.virtualspeakers. When I select one of the coll files or hrtf files in the umenu I get a message that they cannot be found. I have placed the folder containing SPAT in my Max search path, but am still having this issue. Any help would be appreciated.
Thanks.

OK. I Think there is no problem with the abstraction.
However, your Max/MSP seems to be running at 48000 Hz sampling rate.

As previously mentioned, most of the HRTF files are only available at 44100 Hz.
For instance, the Spat packages contains a ‘2b-1018-44100.coll’ file but no ‘2b-1018-48000.coll’.
So it makes sense that the file cannot be found.

If you really need to run at 48 kHz, you can have a look at the folder ‘ircam-spat/media/hrtf/transpan/binaural’ which contains a few files for this sampling rate.
(The naming convention used for these files is however slightly different, so you cannot use the spat.hrtf.selection abstraction to load them. You would have to build your own abstraction for that. I can help if needed).

Thank you! You correctly identified my problem. I had checked that the audio files that I was opening were 44.1, but I had not checked to see if Max was running in 44.1. Max was set at sampling rate of 4800! When re-set to 44.1 the .coll files load seamlessly. Thanks for the help.
Scott

I’m working at 96KHz, what solution would the use of hrtfs abstraction?
If I load directly binaural files to spat.spat ~ (@panning binaural @decoding null) using the “load” message (eg.:”load filename.hrtf” ) that’s work, even if at 96KHz, but if I load directly transaural files to spat.spat ~(@panningbinaural @transauraldecoding) does not work.

Thanks
Best
Raúl

Attachments:

– at the moment, hrtf files are mostly provided for 44.1 or 48 kHz. Not for 96 kHz.
I recommend to use the proper filters corresponding to the used sampling rate,
although loading filters with a different sampling rate does not throw an error.

– we will soon work on 96 kHz filters and they will be provided in future releases.

– spat supports different transaural algorithms. Each algorithm requires a specific set of filters.
The files currently shipped in /ircam-spat/media/hrtf/transaural/biquads correspond to the so-called “shuffler symmetric” implementation.
The files currently shipped in /ircam-spat/media/hrtf/transaural/fir correspond to the so-called “feedforward asymmetric” implementation.
I know, this is not really logical, but we’ll definitely clarify this in further releases.

– Attached is a patch that demonstrates how to load the different kind of filters.

Hope this helps,
T.

— Pasted Max Patch, click to expand. —

Copy all of the following text.Then, in Max, select New From Clipboard.

Everything is very clear.
We wait for future versions.
I know it’s not ideal to work with a different sampling frequency that the IR files (do not know how the system reacts, resampling…), but using that x2 sample rate of hrtf file, the artifacts are minimized (44.1 hrtf file— Sampling rate 88.2 kHz or 48.0 hrtf file— Sampling rate Khz 96). I have to test the possible occurrence of aliasing.

Thank you for your patch, and for your explanation about transaural setting filters.